Manejo quirúrgico de bad split bilateral en cirugía ortognática / Surgical management of bilateral bad split during orthognathic surgery

El bad split es un término clínico que refiere a una fractura no planificada que ocurre al momento de realizar una osteotomía sagital de rama mandibular (OSRM). Afecta aproximadamente al 2,3% de los pacientes y se han descrito factores de riesgo tales como la presencia de terceros molares mandibulares, edad avanzada al momento de la cirugía, técnica de osteotomía inadecuada, entre otros. Se recomienda efectuar manio-bras preventivas para evitar la aparición de patrones de fractura no deseados al realizar la OSRM. Sin embargo, al momento de pesquisar un bad split, éste debe ser tratado por un equipo capacitado y de manera oportuna para evitar retardo en la consolidación, infecciones y secuestros óseos que puedan comprometer los resultados de la cirugía. En este artículo se presenta el manejo de un caso clínico de bad split bilateral intraoperatorio por el Servicio de Cirugía Maxilofacial del Hospital San José, enfatizando su tratamiento quirúrgico.

Bad Split is a clinical term referring to an unplanned fracture that occurs during the bilateral sagittal split osteotomy (BSSO). It affects approximately 2,3% of the patients undergoing orthognathic surgery and several risk factors have been described such as the presence of mandibular third molars, advanced age at the moment of orthognathic surgery, inadequate osteotomy technique, etc. Preventive maneuvers are recommended in order to avoid the appearance of undesired fracture patterns during BSSO. However, if a bad split is detected it must be managed and treated by a qualified team to avoid further complications such as delayed bone consolidation, bone infection and necrosis. In this article we present the management of a case of bilateral bad split by the Maxillofacial Surgery Service of Hospital San José, emphasizing on its surgical treatment.

Incidence of inferior alveolar nerve sensory deficit and intra-operative nerve encounters after advancement of retrognathic mandible – A cross-sectional survey study

Aims and Objectives: The aim of the current cross?sectional study was to conduct a survey among the oral and maxillofacial surgeons of South India regarding their experiences of incidence of inferior alveolar nerve (IAN) neurosensory deficit after bilateral sagittal split osteotomy (BSSO) for correction of mandibular retrognathism and to assess the intra?operative nerve encounters and its effect on the inferior alveolar neurosensory deficit (NSD), 6 months post?operatively. Materials and Methods: A self?administered questionnaire (SAQ) was prepared using Google Forms (Google Inc.) and sent to the prospective participants through various social media outlets such as Facebook, WhatsApp groups etc., of the maxillofacial surgery specialty for a period of 3 months. SAQ from surgeons with more than 5 years of experience in orthognathic surgery were included. Results: The incidence of NSD post?BSSO advancement surgery from 859 cases after 6 months was 15.1% (130). After splitting the mandible, the IAN was seen in the proximal fragment in 472 sites and needed dissection. The nerve was transected and neurorrhaphy was carried out in 26 sites. A Chi?square test was used to analyse the qualitative variables. The IAN was not visible post?osteotomy in 140 sites and in the distal fragment in 1080 sites. These groups had decreased incidence of NSD. The NSD was significantly higher in cases where the nerve was transected and sutured, P value <0.001 as compared with the other nerve status, followed by the nerve in the proximal fragment needing dissection. Conclusion: The IAN status intra?operatively can be assumed to have a significant role in persisting NSD

Como Predecir el Cambio del Tejido Blando Facial Luego de Cirugía Ortognática. Una Revisión de la Literatura / How to Predict Facial Soft Tissue Change After Orthognathic Surgery. A Literature Review

RESUMEN: Habitualmente los pacientes buscan estética en un tratamiento de ortodoncia, y al tener que someterse a una cirugía ortognática, lo que más les preocupa es cómo se verán luego de ésta. Hoy en día existe variados softwares para mostrar una imagen virtual del resultado del tejido esquelético y blando luego de una cirugía, pero no se ha llegado a consenso de que tan fiables son, ya que cada ortodoncista puede utilizar distintos métodos de medición. En este estudio queremos realizar una revisión bibliográfica para evaluar el efecto de la cirugía Lefort I y sagital bilateral de rama sobre el tejido blando del tercio medio e inferior en pacientes que han tenido tratamiento ortodóncico. Para así, en un futuro, poder predecir el comportamiento del tejido blando a través del tratamiento quirúrgico.

ABSTRACT: Usually patients seek aesthetics in orthodontic treatment, and having to undergo orthognathic surgery, what they are most concerned about is how they will look after it. Nowadays there are various softwares to show a virtual image of the result of skeletal and soft tissue after surgery, but no consensus has been reached on how reliable they are, since each orthodontist can use different measurement methods. In this study, we want to carry out a bibliographic review to evaluate the effect of Lefort I and bilateral sagittal branch surgery on the soft tissue of the middle and lower third in patients who have undergone orthodontic treatment. Thus, in the future, to be able to predict the behavior of soft tissue through surgical treatment.

Hybrid fixation in the bilateral sagittal split osteotomy for lower jaw advancement

Miniplate and screw fixation has been widely used in bilateral sagittal split osteotomy, but some issues remain unclear concerning its lack of rigidity when compared to Spiessl's bicortical technique. This paper demonstrates the hybrid fixation technique in a case report. A 34-year-old female patient underwent a double jaw surgery with counter-clockwise rotation of the mandible fixed using the hybrid fixation technique. The patient evolved well in the postoperative period and is still under follow up after 14 months, reporting satisfaction with the results and no significant deviation from the treatment plan up to now. No damage to tooth roots was done, maxillomandibular range of motion was within normality and regression of the inferior alveolar nerve paresthesia was observed bilaterally. The hybrid mandibular fixation is clearly visible in the panoramic and cephalometric control radiographs. It seems that the hybrid fixation can sum the advantages of both monocortical and bicortical techniques in lower jaw advancement, increasing fixation stability without significant damage to the mandibular articulation and the inferior alveolar nerve. A statistical investigation seems necessary to prove its efficacy.

The study of stability of absorbable internal fixation after mandibular bilateral sagittal split ramal osteotomy

INTRODUCTION: To evaluate the skeletal stability after a bilateral sagittal split osteotomy (BSSO) setback of the mandible fixed with a biodegradable internal fixation device or metal internal fixation device. MATERIALS AND METHODS: Thirty consecutive patients underwent mandibular setback via BSSO. Fifteen patients were fixed with a biodegradable internal fixation device or metal internal fixation device respectively. Posteroanterior (PA) and lateral cephalograms were taken preoperatively and at two days, 5.5 months and 14.5 months postoperatively. The relevant skeletal points were traced and digitized to evaluate the skeletal changes postoperatively. The relapse rates were analyzed and compared statistically. RESULTS: There was no statistically significant differences in postoperative stability between the two groups.(P<0.05) CONCLUSION: The biodegradable internal fixation device may make an effective device alternative to a metal internal fixation device for setback BSSO.